• Title/Summary/Keyword: trap factor

검색결과 153건 처리시간 0.033초

$a-Si_{1-x}Ge_x:H$ 화합물(化合物) p-i-n 태양전지(太陽電池)의 물리(物理) 및 전류밀도(電流密度)-전압(電壓) 특성(特性) (Physics and current density-voltage characteristics of $a-Si_{1-x}Ge_x:H$ alloy p-i-n solar cells)

  • 권영식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1994년도 하계학술대회 논문집 C
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    • pp.1435-1438
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    • 1994
  • The effects of Ge composition variation in $a-Si_{1-x}Ge_x:H$ alloy p-i-n solar cells on the physical properties and current density-voltage characteristics are analyzed by a new simulation modelling based on the update published experimental datas. The simulation modelling includes newly formulated density of gap density spectrum corresponding to Ge composition variation and utilizes the newly derived generation rate formulars which include the reflection coefficients and can apply to multijunction structures as well as single junction structure. The effects in $a-Si_{1-x}Ge_x:H$ single junction are analyzed through the efficiency, fill factor, open circuit voltage, short circuit current density, free carriers, trap carriers, electric field, generation rate and recombination rate. Based on the results analyzed in single junction structure, the applications to multiple junction structures are discussed and the optimal conditions reaching to a high performance are investigated.

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진무탕(眞武湯)이 흰쥐의 대퇴골 골절 치유에 미치는 실험적 연구 (The Healing Effect of Jinmu-tang (Zhenwu-tang) in Femur Fractured Rats)

  • 박정오;오민석
    • 한방재활의학과학회지
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    • 제30권2호
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    • pp.19-35
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    • 2020
  • Objectives The aim of this study is to evaluate the fracture healing effect of Jinmu-tang (JM) on femur fractured rats. Methods Rats were randomly divided into 5 groups (normal, control, positive control, JM extract with low concentration and JM extract with high concentration). All group except normal group went through both femur fracture. Normal and control group received no treatment at all. Positive control group were medicated with tramadol (20 mg/kg) once a day for 14 days. Experimental group was orally medicated with JM extract (10 mg/kg for low concentration, 50 mg/kg for high concentration) once a day for 14 days. In order to investigate fracture healing process, plasma and serum were obtained. Also, micro-computed tomography was conducted to see the frature site visually. Immunohistochemistry for transforming growth factor-β1, Ki67, alkaline phosphatase, runt-related transcription factor 2, receptor activator of nuclear factor kappa-β, tartrate resistant acid phosphatase was conducted to observe bone healing progress after 14 days since fracture occured. Aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen and creatinine levels were measured in plasma, for hepatotoxicity and nephrotoxicity of JM extract. Osteocalcin was measured to observe activity of osteoblast. Results Through Micro-CT, more fracture healing was observed on both experimental group than control and positive control group. Through Hematoxylin & Eosin and safranin O staining showed bone cell proliferation and bone formation in the experimental group. RANK was significantly increased in the experimental groups. JM with high concentration showed statistically significant of TGF-β and Osteocalcin. NO, TRAP and ALP were not significantly changed. Liver toxicity was not significantly observed. Creatinine significantly increased in both experimental groups after 28 days. Conclusions As described above, JM extract showed anti-inflammatory effect, promoted fracture healing by stimulating the bone regeneration factor, and showed little hepatotoxicity and nephrotoxicity. In conclusion, JM extract can promote fracture healing and it can be used clinically to patients with fracture.

Effect of caspases and RANKL induced by heavy force in orthodontic root resorption

  • Minato, Yukari;Yamaguchi, Masaru;Shimizu, Mami;Kikuta, Jun;Hikida, Takuji;Hikida, Momoko;Suemitsu, Masaaki;Kuyama, Kayo;Kasai, Kazutaka
    • 대한치과교정학회지
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    • 제48권4호
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    • pp.253-261
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    • 2018
  • Objective: Orthodontic root resorption (ORR) due to orthodontic tooth movement is a difficult treatment-related adverse event. Caspases are important effector molecules for apoptosis. At present, little is known about the mechanisms underlying ORR and apoptosis in the cementum. The aim of the present in vivo study was to investigate the expression of tartrate-resistant acid phosphatase (TRAP), caspase 3, caspase 8, and receptor activator of nuclear factor kappa-B ligand (RANKL) in the cementum in response to a heavy or an optimum orthodontic force. Methods: The maxillary molars of male Wistar rats were subjected to an orthodontic force of 10 g or 50 g using a closed coil spring. The rats were sacrificed each experimental period on days 1, 3, 5, and 7 after orthodontic force application. And the rats were subjected to histopathological and immunohistochemical analyses. Results: On day 7 for the 50-g group, hematoxylin and eosin staining revealed numerous root resorption lacunae with odontoclasts on the root, while immunohistochemistry showed increased TRAP- and RANKL-positive cells. Caspase 3- and caspase 8-positive cells were increased on the cementum surfaces in the 50-g group on days 3 and 5. Moreover, the number of caspase 3- and caspase 8-positive cells and RANKL-positive cells was significantly higher in the 50-g group than in the 10-g group. Conclusions: In our rat model, ORR occurred after apoptosis was induced in the cementum by a heavy orthodontic force. These findings suggest that apoptosis of cementoblasts is involved in ORR.

갈색거저리 유충 에탄올 추출물이 RANKL에 의해 유도되는 파골세포 분화에 미치는 영향 (Inhibitory Effects of Tenebrio molitor Larvae Ethanol Extract on RANKL-Induced Osteoclast Differentiation)

  • 서민철;백민희;이화정;신용표;이준하;김인우;김미애;황재삼
    • 생명과학회지
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    • 제30권11호
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    • pp.983-989
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    • 2020
  • 파골세포에 의한 뼈의 재흡수와 조골세포에 의한 뼈 형성의 균형은 뼈 건강에 매우 중요한 요소이다. 따라서 이들의 불균형은 골다공증, 골연화증 및 골석화증과 같은 다양한 골 질환을 유발할 수 있다. 특히 파골세포의 기능이 비정상적으로 항진된 경우 골 파괴가 증가되어 골다공증이 야기되며 이런 현상은 류마티스 관절염 같은 염증성 질환의 골 소실과 밀접한 연관이 있다. 그러나 현재 사용중인 골 흡수 억제제는 장기간 사용시 부작용이 보고되고 있어 천연물 소재를 기반으로한 새로운 골 흡수 억제제 개발이 요구되고 있다. 따라서 본 연구에서는 갈색거저리 유충 에탄올 추출물이 RANKL에 의해 유도되는 파골세포 분화에 미치는 영향을 확인하고 그 작용기작을 구명하고자 하였다. 갈색거저리 유충 에탄올 추출물이 파골세포 분화에 미치는 영향을 조사하기 위하여 RAW264.7 세포에 RANKL을 단독 처리 및 추출물과 함께 5일간 처리한 후 TRAP 활성을 비교하였다. 그 결과 RANKL에 의해 증가한 파골세포 분화는 갈색거저리 유충 추출물 2 mg/ml 농도까지 세포독성 없이 농도 의존적으로 감소하는 것을 확인할 수 있었다. 또한 갈색거저리 추출물이 TRAP, NFATc1 및 CtsK와 같은 파골세포 분화마커 유전자 및 단백질 발현량에 미치는 변화를 확인한 결과, RANKL 처리에 의해 현저히 증가한 이들 유전자가 갈색거저리 추출물에 의해 현저하게 감소하는 것을 확인하였다. 또한 갈색거저리 추출물의 파골세포 분화 억제작용기작을 확인한 결과 mitogen activated protein kinases (MAPKs)중 p38의 신호 전달 억제 기작을 통하여 파골세포 분화가 억제됨을 확인 할 수 있었다. 이러한 결과로 보아 갈색거저리 유충 에탄올 추출물 및 그 생리활성 물질들은 골다공증과 같은 골 질환 치료 및 예방을 위한 잠재적 기능성 소재로 사용될 수 있음을 확인하였다.

Crystallographic study of in-plane aligned hybrid perovskite thin film

  • 이린;김세준;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.163.1-163.1
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    • 2016
  • Lead halide perovskites CH3NH3PbX3 (X=Cl, Br, I) have received great interest in the past few years because of their excellent photoelectronic properties as well as their low-cost solution process. Their theoretical efficiency limit of the solar cell devices was predicted around 31% by a detailed balance model for the reason that exceptional light-harvesting and superior carrier transport properties. Additionally, these excellent properties contribute to the applications of optoelectronic devices such as LASERs, LEDs, and photodetectors. Since these devices are mainly using perovskite thin film, one of the most important factor to decide the efficiency of these applications is the quality of the film. Even though, optoelectrical devices are composed of polycrystalline thin film in general, not a single crystalline form which has longer carrier diffusion length and lower trap density. For these reasons, monodomain perovskite thin films have potential to elicit an optimized device efficiency. In this study, we analyzed the crystallography of the in-plane aligned perovskite thin film by X-ray diffraction (XRD) and selected area electron diffraction (SAED). Also the basic optic properties of perovskites were checked using scanning electron microscopy (SEM) and UV-Vis spectrum. From this work, the perovskite which is aligned in all directions both of out-of-plane and in-plane was fabricated and analyzed.

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Differences in Moth Diversity in Two Types of Forest Patches in an Agricultural Landscape in Southern Korea - Effects of Habitat Heterogeneity -

  • Choi, Sei-Woong;Park, Marana;Kim, Hui
    • Journal of Ecology and Environment
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    • 제32권3호
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    • pp.183-189
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    • 2009
  • This research focused on the effects of fragmentation on moth diversity in an agricultural land-scape by comparing moth species richness and abundance between hillocks and young secondary forests. We examined five sites from the southwestern part of South Korea: three sites from hillock forest and two from secondary forest. We collected moths bi-weekly from April to October for a 2-year period (2006-2007) with a UV light trap that usually attracts moths within 30 meters. Tree species richness and abundance in $20m{\times}20m$ plots at each moth sampling site showed a substantial difference in tree diversity between the two types of forest habitats. The total abundance and richness of moth species were higher in secondary forests (541 species with 4,998 individuals) than in hillock forests (423 species with 3,913 individuals), irrespective of the distance among the sites. An ordination analysis with NMDS showed that habitat is the most important factor of grouping sites. The food preferences of the dominant moth species i,n each habitat were closely related to the habitat type.

Plasticity of rice to water extremes: Farmers' genes to mechanisms

  • Bailey-Serres, Julia
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.5-5
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    • 2017
  • Too little and too much water due to climatic events is a significant cause of global food insecurity. Crops are less productive under water-limited conditions and all major crops, with the exception of rice (Oryza sativa), die within a few days of complete submergence. To complement our studies on genes such as SUB1A, (an ERF-VII transcription factor that provides robust submergence tolerance) and AG1 (a TREHALOSE 6-P PHOSPHATASE that promotes establishment of young seedlings underwater), we have retooled INTACT (${\underline{I}}solation$ of ${\underline{N}}uclei$ ${\underline{TA}}gged$ in specific ${\underline{C}}ell$ ${\underline{T}}ypes$) and TRAP (${\underline{T}}ranslating$ ${\underline{R}}ibosome$ ${\underline{A}}ffinity$ ${\underline{P}}urification$) for rice. These technologies enable us to follow dynamics in chromatin, nuclear pre-mRNAs and ribosome-bound mRNAs in meristems and diverse cell types. With these technologies we can better interpret responses to stresses and reestablishment of homeostasis. These include stress acclimation strategies involving changes in metabolism and development, such as dynamics in suberin deposition in sub-epidermal layers of roots that limit water loss under drought and oxygen escape during waterlogging. Our new data uncover dynamic and reversible regulation at multiple levels of gene regulation and provide new insights into processes of stress resilience. Supported by US NSF-PGRP Plasticity (IOS-1238243), Secretome (IOS-1546879) and REU (DBI-146129) grants.

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A Novel PPARγ Agonist, SP1818, Shows Different Coactivator Profile with Rosiglitazone

  • Park, Yun-Sun;Choi, Ji-Won;Kim, Kun-Yong;Lim, Jong-Seok;Yoon, Suk-Joon;Yang, Young
    • Biomolecules & Therapeutics
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    • 제18권1호
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    • pp.77-82
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    • 2010
  • Peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is a ligand-activated transcription factor that is used as a target for anti-diabetic drug development. In a search for novel PPAR${\gamma}$ agonists, the $\beta$-carboxyethyl-rhodanine derivative SP1818 was identified. We report here the characteristics of SP1818 as a selective PPAR${\gamma}$ agonist. In transactivation assays, SP1818 selectively activated PPAR${\gamma}$, but the degree of PPAR${\gamma}$ stimulation was less than with $1{\mu}M$ rosiglitazone. SP1818 also stimulated glucose uptake in a concentration-dependent manner. The adipocyte differentiation markers adiponectin, scavenger receptor CD36 and aP2 were weakly induced by treatment with SP1818, and TRAP220 subunit was specifically recruited into PPAR${\gamma}$ activated by rosiglitazone but not PPAR${\gamma}$ activated by SP1818.

다목적 저류지의 수질개선을 위한 설계과정 및 적용에 관한 연구 - 남악 신도시 개발지를 대상으로 - (A Study on the Application and Design Procedure of Multi-Purpose Wet Detention Ponds for Improving Water Quality - Case Study of NamAk New Town Development Area -)

  • 우창호
    • 한국환경복원기술학회지
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    • 제7권1호
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    • pp.97-109
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    • 2004
  • The disposal of stormwater is one of the major problems in urban water management. One method of reducing peak runoff rates and other detrimental impacts of stormwater is detention storage. Detention ponds as a water quality control alternatives have been investigated by a number of researchers. Recognizing multiple roles such as flood peak attenuation, pollution removal and aesthetic enhancement, the design and management of detentions ponds deserve more research. The purpose of this research is to establish design criteria wet detention ponds to improve water quality. Water quality in detention pond discharge might be improve with physical, chemical and biological alterations. Physical alteration was focused in this study. There are several methods for estimating the suspended solid control capability of wet detention ponds. Existing models of suspended solids removal are based on sedimentation and gravity settling theory. The pollutant trap efficiency of pond is a function of several interrelating factors. Detention time is the most important factor, because it determine gravity settling quantities of pollutants. Desirable modification of physical factors for improvement of water quality in wet detention ponds are volume ratio, area ratio, length to width ratio, depth, out let location, bottom soil type. In order to apply design procedure in actual site, Namak new town development area was selected.

In Vivo Expression of the PTB-deleted Odin Mutant Results in Hydrocephalus

  • Park, Sunjung;Lee, Haeryung;Park, Soochul
    • Molecules and Cells
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    • 제38권5호
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    • pp.426-431
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    • 2015
  • Odin has been implicated in the downstream signaling pathway of receptor tyrosine kinases, such as the epidermal growth factor and Eph receptors. However, the physiologically relevant function of Odin needs to be further determined. In this study, we used Odin heterozygous mice to analyze the Odin expression pattern; the targeted allele contained a ${\beta}$-geo gene trap vector inserted into the 14t intron of the Odin gene. Interestingly, we found that Odin was exclusively expressed in ependymal cells along the brain ventricles. In particular, Odin was highly expressed in the subcommissural organ, a small ependymal glandular tissue. However, we did not observe any morphological abnormalities in the brain ventricles or ependymal cells of Odin null-mutant mice. We also generated BAC transgenic mice that expressed the PTB-deleted Odin (dPTB) after a floxed GFP-STOP cassette was excised by tissue-specific Cre expression. Strikingly, Odin-dPTB expression played a causative role in the development of the hydrocephalic phenotype, primarily in the midbrain. In addition, Odin-dPTB expression disrupted proper development of the subcommissural organ and interfered with ependymal cell maturation in the cerebral aqueduct. Taken together, our findings strongly suggest that Odin plays a role in the differentiation of ependymal cells during early postnatal brain development.